KR20100018175A - Method for processing aqueous polyurethane dispersed solution with excellent suncream and abrasion resistance containing hydroxy group, and soft coating composition containing the same - Google Patents

Abstract

PURPOSE: A method for processing aqueous polyurethane dispersion is provided to ensure excellent adhesion at a room temperature, sunscreen property, and abrasion resistance, and to obtain a soft coating composition. CONSTITUTION: A method for processing aqueous polyurethane dispersion containing a hydroxy group comprises the steps of: (i) reacting a polyol mixture mixed with at least two kinds selected from polycaprolactone, polycarbonate, polysiloxane glycol or polytetramethylene glycol, with polyisocyanate; (ii) reacting the reactant obtained from step (i) with polyamine having sulfonate to prepare polyurethane and then dispersing the polyurethane in water to prepare a polyurethane dispersion; and (iii) reacting the dispersion obtained from step (ii) with a polyfunctional epoxy compound with 100-300 number average molecular weight to prepare a aqueous polyurethane dispersion containing a hydroxy group.

Description

Method for preparing a hydroxyl group-containing aqueous polyurethane dispersion having excellent sunscreen resistance and abrasion resistance, and a soft coating composition containing the same {Method for processing aqueous polyurethane dispersed solution with excellent suncream and abrasion resistance containing hydroxy group, and soft coating composition containing the same}

The present invention relates to a method for preparing a hydroxy group-containing aqueous polyurethane dispersion for soft coating, and to a soft coating composition containing the same. More specifically, (a) reacting a polyol mixture having a specific component as a main chain with a polyisocyanate; (b) preparing a high molecular weight polyurethane dispersion by reacting with a polyamine having a sulfonic acid salt to prepare a high molecular weight polyurethane and then dispersing it with water; And (c) reacting the dispersion with a monofunctional epoxy compound having a number average molecular weight of 100 to 300 to produce an aqueous polyurethane containing a hydroxy group in the polyurethane chain. It relates to a manufacturing method and a soft coating composition containing the same.

Aqueous polyurethane dispersions have been used in many applications because of their environmentally friendly and dry properties with water. This technique is based on the preparation of high molecular weight polyurethane polymer particles in water. As the water leaves the coated coating, the particles coalesce to form the final uncrosslinked film. Such coatings are generally poor in terms of chemical resistance and mechanical durability, in particular so-called 'soft' coatings, compared to single or bicomponent crosslinked films. One variation of this technique is to prepare an aqueous polyurethane dispersion with an excess of hydroxyl groups by mixing with an aqueous polyurethane dispersion containing no hydroxy groups. These two kinds of aqueous polyurethane dispersions can be combined with water dispersible polyisocyanates to form two-component aqueous soft coatings with improved general performance. However, such a coating has a problem that the sunscreen resistance, wear resistance, etc. are vulnerable due to the aqueous urethane dispersion containing no hydroxyl group. Conventional typical aqueous dispersions used in soft coatings are described in US Pat. Nos. 6,211,286, 6,254,937 and 6,414,079; And US Patent Publication Nos. 2002/0137828 and 2002/0147253; And Korean Unexamined Patent Publication No. 2008-0004316.

Accordingly, the present inventors have tried to improve the sunscreen resistance and the abrasion resistance of the aqueous polyurethane dispersion, by reacting a polyol mixture having a specific component as a main chain with a polyisocyanate and reacting it with a monofunctional epoxy compound having a number average molecular weight of 100 to 300 The present invention has been accomplished by discovering that a hydroxyl group-containing aqueous polyurethane dispersion having excellent sunscreen resistance and abrasion resistance can be prepared.

Accordingly, it is an object of the present invention to provide a method for preparing a hydroxyl group-containing aqueous polyurethane dispersion for soft coating having excellent sunscreen resistance and abrasion resistance.

It is also an object of the present invention to provide a soft coating composition containing the hydroxy group-containing aqueous polyurethane dispersion.

In order to achieve the above object, in the present invention

1) reacting a polyol mixture of two or more kinds of polyols including polycaprolactone, polycarbonate, polysiloxane glycol or polytetramethylene glycol with polyisocyanate;

2) preparing a polyurethane by reacting the reactant of step 1 with a polyamine having a sulfonic acid salt, and then dispersing the polyurethane in water to prepare a polyurethane dispersion; And

3) reacting the dispersion solution of step 2) with a monofunctional epoxy compound having a number average molecular weight of 100 to 300 to prepare an aqueous polyurethane containing a hydroxyl group in the polyurethane chain.

Provided is a method for preparing a hydroxyl group-containing aqueous polyurethane dispersion for soft coating.

In addition, the present invention provides a composition for a soft coating containing the hydroxyl group-containing aqueous polyurethane dispersion.

The hydroxyl group-containing aqueous polyurethane dispersion according to the present invention was excellent in room temperature adhesion, sunscreen resistance and abrasion resistance, by which it was possible to provide a soft coating composition excellent in sunscreen resistance and abrasion resistance.

Hereinafter, the present invention will be described in more detail.

The present invention relates to a method for producing a hydroxyl group-containing aqueous polyurethane dispersion for soft coating having excellent sunscreen resistance and abrasion resistance.

First, the components used to prepare the hydroxyl group-containing aqueous polyurethane dispersion according to the present invention will be described.

(a) specific ingredients By main chain  doing Polyol  Mixture and Polyisocyanate

It is preferable to mix and use 2 or more types of polyols containing polycaprolactone, polycarbonate, polysiloxane glycol, or polytetramethylene glycol as a polyol used for manufacture of the water-based polyurethane resin of this invention. More preferably, a mixture of polycaprolactone, polycarbonate and polysiloxane glycol or a mixture of polycaprolactone, polycarbonate or polytetramethylene glycol may be used. In the aqueous polyurethane resin of the present invention, the content of the polyol is preferably contained in an amount of 60 to 80 parts by weight based on the solid content of the aqueous polyurethane resin.

Specifically, the polyol containing polycaprolactone is a polyester produced by reacting ε-caprolactone with dimethylol propionic acid or dimethylol butanoic acid with diol. Examples of diols useful in the present invention include ethanediol; 2- and 1,3-propane diols; 1,2-, 1,3-1,4-butanediol; 1,5-pentanediol; 1,6-hexanediol; Neopentyl glycol; Cyclohexane-1,4-dimethanol; 1,2- and 1,4-cyclohexanediol; 2-ethyl-2-butylpropanediol; 2-methyl-propane-1,3-diol; And diols containing ether oxygen. Examples thereof include diethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene glycol, tripropylene glycol, polyethylene, polypropylene or polybutylene glycol; Bisphenol A; And as a polyol containing tetrabromo bisphenol A, the polyol manufactured by reacting 1, 4- butanediol and 1, 6- hexanediol individually or in mixture is preferable. The polyol containing polycaprolactone is a polyol containing carboxylic acid in the main chain and has a molecular weight of 600 to 1,500, and finally serves to introduce a hydroxyl group into the main chain by reacting with a monofunctional epoxy compound.

Polyols comprising polycarbonates are esters of carbonic acid produced by the reaction of dicarbonates (eg diphenyl carbonate, dimethyl carbonate or phosgene) with diols. Examples of useful diols include ethanediol; 2- and 1,3-propane diols; 1,2-, 1,3-1,4-butanediol; 1,5-pentanediol; 1,6-hexanediol; Neopentyl glycol; Cyclohexane-1,4-dimethanol; 1,2- and 1,4-cyclohexanediol; 2-ethyl-2-butylpropanediol; 2-methyl-propane-1,3-diol; And diols containing ether oxygen. Examples thereof include diethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene glycol, tripropylene glycol, polyethylene, polypropylene or polybutylene glycol; Bisphenol A; And a polyol containing tetrabromo bisphenol A having a number average molecular weight of 1,000 to 2,500, and a polyol prepared by reacting 1,4-butanediol, 1,6-hexanediol, and neopentylglycol alone or in combination of two or more thereof. This is preferred.

The polyol containing polysiloxane glycol is a polysiloxane polyol having a hydroxyl group of 1.5 or more functional groups represented by the following general formula (1). In particular, the polysiloxane glycol may have superior compatibility and maximize water resistance than a siloxane polyol having a linear structure in which a hydroxyl group is bonded to the siloxane bond terminal.

R-Si (CH ₃ ) _2- (OSi (CH ₃ ) ₂ ) _n -OSi (CH ₃ ) ₂ -XY

Wherein R is an unsubstituted alkyl radical having 1 to 6 carbon atoms,

N, the repeating unit of siloxane, is a number from 7 to 10,

X may contain propylene oxide, butylene oxide units in addition to ethylene oxide, preferably propylene oxide,

Y is a triol or higher polyol, and is preferably trimethylolpropane as a polyol containing trimethylolethane, trimethylolpropane, triethylolpropane.

The polyol containing polytetramethylene glycol is a polyether polytetramethylene glycol polymerized by polyaddition by ring-opening tetrahydrofuran and it is preferable that number average molecular weights are 1,000-2,500.

There is no restriction | limiting in particular in the organic polyisocyanate used for manufacture of the water-based polyurethane resin of this invention, It is possible to use the aliphatic polyisocyanate, alicyclic polyisocyanate, aromatic polyisocyanate which are used normally, and these alone or in mixture.

Specific examples of the polyisocyanate compound include 1,4-tetramethylenediisoisanate, 1,6-hexamethylene diisocyanate, 1,12-dodecamethylene diisocyanate, cyclohexane-1,3- or 1,4- Diisocyanate, 1-isocyanato-3-isocyanatomethyl-3,5,5-trimethylcyclohexane (isophorone diisocyanate; IPDI), bis- (4-isocyanatocyclohexyl) methane (hereinafter, “ Hydrogenated MDI ”), 2- or 4-isocyanatocyclohexyl-2-isocyanatocyclohexyl methane, 1,3- or 1,4-bis (isocyanatomethyl) -cyclohexane, bis- ( 4-isocyanato-3-methylcyclohexyl) methane, 1,3- or 1,4-α, α, α ', α'-tetramethylxylene diisocyanate, 2,4- or 2,6-toluene Diisocyanate, 2,2-, 2,4- or 4,4-diisocyanatodiphenylmethane (MDI), 1,5-naphthalenediisocyanate, ρ- or m-phenylenediisocyanate, xylenedi Isocyanate and diphenyl-4,4-diisocyanate. Among these, 2, 4- toluene diisocyanate and 2, 6-toluene diisocyanate are used as an isomer of 65:35 or 80:20 ratio, respectively.

 Among the above compounds, it is preferable to use an aliphatic or cycloaliphatic diisocyanate compound from the viewpoint of mechanical properties and yellowing resistance, and it is more preferable to mix and use an aliphatic and cycloaliphatic isocyanate compound from the viewpoint of cohesion and adhesion. On the other hand, it is preferable to use a bifunctional or lower polyisocyanate from the viewpoint of obtaining a linear polyurethane resin having more suitable cohesion and adhesion. The content of polyisocyanate in the aqueous urethane resin of the present invention is preferably contained in a proportion of 20 to 30% by weight based on the solid content of the aqueous polyurethane resin.

(b) Sulfonate  Number average molecular weight of 200 to 600 Polyamine

Examples of polyamines having a number average molecular weight of 200 to 600 having a sulfonic acid metal salt used in the preparation of the aqueous polyurethane resin of the present invention include α, ω-polypropylene glycoldiamine-sulfo containing metals such as Na, K, Li or Ca. The use of Nated allows water to be used even in small amounts, has a good wetting effect on the material and improves adhesion. In addition, there is an advantage to increase the pot life (pot life) of the two-component coating for soft coating. In the present invention, the content of sulfonic acid ion groups in the polyamine is preferably contained in a ratio of 1 to 9% by weight, more preferably 1 to 6% by weight relative to the solid polyurethane resin solids.

(c) the number average molecular weight of 100-300 Monofunctional  Epoxy compound

The monofunctional epoxy compound having a molecular weight of 100 to 300 used in the present invention provides a hydroxyl group reactive group of the polyurethane resin obtained above and also serves to bind with a bicomponent polyisocyanate. Specific examples of the monofunctional epoxy compound correspond to the formula (2).

Wherein R ₁ is H or —CH ₃ ,

R ₂ is —C _n H _{2n +1} , n = 1 to 3,

R ₃ is -C _n C _{2n +1,} a n = 1~4.

Of the above compounds, R ₁ is -CH ₃ , R ₂ is -C ₃ H ₇ , R ₃ is -C ₄ H _{9 The} compound is most preferred, 1 to 5% by weight relative to the solid content of the aqueous urethane resin, Preferably it is used at 0.1 to 3% by weight. If it exceeds the content range, the increase in molecular weight results in low solids and the interface is broken, making aqueous formation impossible. In addition, since the hydroxyl group content that can be crosslinked increases, the softness peculiar to the inferiority falls.

On the other hand, examples of the organic solvent used in the preparation of the aqueous polyurethane resin of the present invention are benzene, toluene, ethyl acetate, acetone, methyl ethyl ketone, diethyl ether, tetrahydrofuran, methyl acetate, acetonitrile, chloroform, methylene chloride , Carbon tetrachloride, 1,2-dichloroethane, 1,1,2-trichloroethane, tetrachloroethylene or N-methylpyrrolidone, and the like, and these may be used alone or in combination. It is preferable to use acetone or methyl ethyl ketone as a solvent with high solubility with a polyurethane resin among the above.

On the other hand, an emulsifier may also be used in the preparation of the aqueous polyurethane resin of the present invention. Examples of the emulsifier include polyoxyethylene polyoxypropylene glycol ether type, polyoxyethylene nonylphenyl ether type, polyoxyethylene octylphenyl ether type, polyoxyethylene lauryl ether type, polyoxyethylene laurate type, polyoxyethylene Nonionic emulsifiers such as alkyl ether type, sorbitan derivative type, polyoxyethylene polycyclic phenyl ether type, anionic emulsifiers such as alkylbenzene sulfonate type, dialkyl succinate sulfonate type, and cationic emulsifier. It is preferable to use a nonionic emulsifier and an anionic emulsifier among the said emulsifiers, and can add 0-5 weight% in solid content ratio with respect to an aqueous polyurethane resin. In the case of using the emulsifier, it is preferable that the emulsion is dispersed after adding it to water in advance during the emulsion dispersion step. However, you may add after completion | finish of an emulsion dispersion process, and these emulsifiers can be used individually or in mixture.

In addition, it is possible to use a catalyst for forming urethane as needed in the production of the aqueous polyurethane resin of the present invention. Representative examples of the catalyst for forming the urethane include various nitrogen-containing compounds such as triethylamine, triethylenediamine and N-methylmorpholine, various metal salts such as potassium acetate, zinc stearate and tin octylate, and dibutyl tin dilaurate. Various organometallic compounds, such as these, are mentioned.

In addition, as a catalyst which can be used in the preparation of the carboxyl group and the monofunctional epoxy compound in the aqueous urethane chain of the present invention, triethylamine, triethylbenzyl ammonium chloride, cetylmethylammonium chloride, chromium acetylacetate, triphenylantimony, tetrabutylammonium chloride, etc. The basic compound of the is mentioned.

The method for preparing the aqueous polyurethane dispersion composition for soft coating having excellent sunscreen resistance and abrasion resistance of the present invention will be described in each step.

(One) Polyol  Mixture and Polyisocyanate  Urethane reaction to prepare polyurethane prepolymer at the end of isocyanate group:

In the preparation of the aqueous urethane dispersion of the present invention, the ratio of the NCO group of the diisocyanate component to the OH group of the polyol component is 1 to 2.5: 1, preferably 1.5 to 2: 1, and the prepolymer reacts appropriately so that the NCO is 3 to 6 In weight percent levels.

Polyurethane prepolymers react appropriately at temperatures from room temperature to 90 ° C., generally from 60 to 85 ° C., and can be prepared without solvents or in the presence of solvents. Catalysts such as tertiary amines or tin salts can be used and the reaction time is 1 It takes about 3 hours. The prepolymer has excellent compatibility with water such as methyl ethyl ketone or acetone, and lowers the viscosity of the polyurethane prepolymer to 100 to 300 cps at 30 ° C. using a solvent free of active hydrogen.

(2) polyurethane of the end of the isocyanate group Prepolymer Polyamines  using Elongated  step:

Polyurethane prepolymers can be chain-stretched using α, ω-polypropyleneglycoldiamine-sulfonated sodium salts of polyamines having a number average molecular weight of 200 to 600 alone or mixed with hydrazine, ethylenediamine, triethylenetetraamine, tetraethylenepentaamine, and the like. Can be.

The polyurethane prepolymer dissolved in acetone or methyl ethyl ketone is reacted with the polyamine at a temperature of 30-50 ° C. to produce a polyurethane-urea solution.

(3) said polyurethane- Urea  Dispersed in water and Monofunctional  Epoxy compound Carboxylic Acids  In response In the main chain  Step of preparing a hydroxy group compound:

Water was slowly added dropwise to the polyurethane-urea polymer for 30 minutes with high dispersion (1000 rpm) and stirred for a further 30 minutes. Then, the monofunctional epoxy compound is prepared by reacting at a temperature of from 55 ° C. to 50 ° C., generally in the presence of a catalyst or a catalyst, and the reaction time is about 3 to 6 hours. An aqueous polyurethane is then produced which contains a hydroxyl group in the polyurethane chain.

(4) vacuum distilling the solvent of the aqueous polyurethane solution:

The solvent present in the aqueous polymer solution is distilled off the solvent in a vacuum of 30 ~ 40 ℃, 700 mmHg.

Through the steps (1) to (4) to prepare an aqueous urethane dispersion for aqueous soft coating.

The aqueous urethane dispersion according to the present invention is prepared by mixing single or different resins.

As another resin that can be mixed with the aqueous urethane dispersion, a low molecular weight polyester-urethane aqueous dispersion may be used, and the resin and the solid content ratio of the present invention are 30 to 60% by weight, preferably 40 to 50% by weight. Use if possible.

The aqueous urethane dispersion for the aqueous soft coating according to the present invention can use coating aids and additives. Examples of auxiliaries and additives of this kind include antifoams, thickeners, pigments, dispersing aids, matting agents, catalysts, anti-filming agents, thickeners, emulsifiers and or additives which can increase the textural effect, as well as mixtures or combinations thereof.

A bifunctional or higher polyisocyanate compound may be used as a crosslinking agent in preparing an aqueous urethane dispersion coating solution for an aqueous soft coating. Examples of the bifunctional or higher polyisocyanate compound include 1,4-tetramethylene diisocyanate, 1,6- Polyisocyanate compounds which consist of trimers, such as hexamethylene diisocyanate, 4, 4- diisoanato diphenyl methane (MDI), xylene diisocyanate, isophorone diisocyanate, these polyisocyanate compounds, ethylene glycol, 1, 3- The compound which has the terminal isocyanate which is comprised by low molecular weight active hydrogen compounds, such as butylene glycol, 1, 4- butylene glycol, polyoxyethylene glycol, and a long chain higher alcohol, is water-soluble is mentioned.

Use of the crosslinking agent improves mechanical properties and chemical resistance of the aqueous polyurethane resin.

The aqueous urethane dispersion for an aqueous soft coating according to the present invention exhibits excellent sunscreen resistance, abrasion resistance, and light resistance, and can be used to realize a "texture effect" on various plastic substrates.

Hereinafter, although an Example and a comparative example are given and this invention is demonstrated in detail, this invention is not limited only to these examples.

[Reference Example 1] Polyester-urethane dispersion 1 containing no hydroxy group

325 g of polyester polyol (trade name: Fomrez E65-56), 12.5 g of trimethylolpropane, 20 g of dimethylolbutanoic acid and 50 g of N-methylpyrrolidone were charged into a 2L reaction vessel equipped with a heater, a cooler, and a stirrer. Dissolve at 100 ° C. for 1 hour. Subsequently, the mixture was cooled to 80 ° C, 42.8 g of nucleated methylene diisocyanate and 0.04 g of dibutyl tin dilaurate were added thereto, and reacted at 100 ° C. until no NCO group was detected. Then, the temperature was cooled to 90 ° C, 8.4 g of dimethylethanolamine was added thereto, stirred at the temperature for 30 minutes, and 541.3 g of deionized water was added thereto, followed by high speed dispersion. The polyester-urethane dispersion thus obtained had a hydroxyl group content (in 100% solids) of 1.55%, 40% by weight of solids, and a viscosity of about 78 cps.

[Reference Example 2] Polyester-urethane dispersion 2 containing no hydroxy group

325 g of polycarbonate polyol (trade name: ETERNACOLL UH-200), 12.5 g of trimethylolpropane, 20 g of dimethylolbutanoic acid and 50 g of N-methylpyrrolidone were added to a 2L reaction vessel equipped with a heater, a cooler, and a stirrer. Dissolve at 100 ° C. for 1 hour. Then, the mixture was cooled to 80 ° C., 42.8 g of nucleated methylene diisocyanate and 0.04 g of dibutyl tin dilaurate were added thereto, and reacted at 100 ° C. until no NCO group was detected. Then, the temperature was cooled to 90 ° C, 8.4 g of dimethylethanolamine was added thereto, stirred at the temperature for 30 minutes, and 541.3 g of deionized water was added thereto, followed by high speed dispersion. The polyester-urethane dispersion thus obtained had a hydroxyl group content (in 100% solids) of 1.55%, 40% by weight of solids, and a viscosity of about 83 cps.

[Reference Example 3] Polyester-urethane dispersion 3 containing no hydroxy group

Bayhydrol ^® PT, a hydroxyl group-containing aliphatic polyester-urethane dispersion having a hydroxyl content (out of 100% solids) of 1.5%, a solids content of 54 to 56% by weight, a pH of 7.2 and a viscosity of 600 mPas at 23 ° C. -355 was used.

Example 1 Hydroxy Group-Containing Aqueous Polyurethane Dispersion

33.5 g of polycaprolactone polyol (trade name: DICAP 600) in which a dimethylol propionic acid is condensation-polymerized in a main chain having a number average molecular weight of 600 in a 2 L reaction vessel equipped with a heater, a cooler and a stirrer, and a polycarbonate polyol having a number average molecular weight of 2000 ( Product name: PCDL L6002) 223.4 g, dibutyl tin dilaurate 0.02 g was added and homogenized at 100 degreeC for 30 minutes. Next, it cooled to 80 degreeC, 77.4g of isophorone diisocyanate and 14.7g of hexamethylene diisocyanate were added, and it was made to react at 80-85 degreeC for 60 minutes. Subsequently, 18.6 g of siloxane polyol (trade name: FM-DA11) containing a bifunctional hydroxy group having a number average molecular weight of 1000 was added thereto, and the reaction was carried out at 85 ° C until the isocyanate content was 4.75%. After cooling to 50 ° C. and completely homogenizing by adding 600 g of anhydrous acetone, 80 ° C. of water, 17.4 g of α, ω-polypropylene glycoldiamine-sulfonated sodium salt and 13.7 g of 80% aqueous hydrazine solution were used at 40 ° C. The mixture was added and reacted at 40 ° C. until no NCO was observed. Next, 513.3 g of water was added thereto, followed by dispersion by high speed stirring. 0.1 g of a catalyst tetrabutylammonium chloride and 8 g of a monofunctional epoxy compound (trade name: Cadura E-10P) were added to this dispersed solution, and the mixture was reacted at 50 to 53 ° C for 5 hours. Acetone was removed under vacuum to give a dispersion having a solids content of 39-41 wt% and a pH of 8.1.

Example 2 Hydroxy Group-Containing Aqueous Polyurethane Dispersion

33.3 g of polycaprolactone polyol (trade name: DICAP 600) in which a dimethylol propionic acid is condensation-polymerized in a main chain having a number average molecular weight of 600 in a 2 L reaction vessel equipped with a heater, a cooler and a stirrer, and a polycarbonate polyol having a number average molecular weight of 2000 ( Trade name: PCDL L6002) 222.3 g, dibutyl tin dilaurate 0.02 g was added and homogenized at 100 ℃. Next, it cooled to 80 degreeC, 77 g of isophorone diisocyanate and 14.6 g of hexamethylene diisocyanate were added, and it was made to react at 80-85 degreeC for 60 minutes. Subsequently, 18.5 g of siloxane polyol (trade name: FM-DA11) containing a bifunctional hydroxy group having a number average molecular weight of 1000 was added thereto, and the mixture was reacted at 85 ° C until the isocyanate content was 4.75%. The mixture was cooled to 50 ° C. and completely homogenized by adding 600 g of anhydrous acetone. Then, a mixture of 80 g of water, 17.4 g of α, ω-polypropylene glycoldiamine-sulfonated sodium salt and 13.6 g of 80% aqueous hydrazine solution at 40 ° C. Was added and reacted at 40 ° C. until no NCO was observed. Then, 513.4 g of water was added thereto, followed by dispersion by high speed stirring. 0.11 g of a catalyst tetrabutylammonium chloride and 10 g of a monofunctional epoxy compound (trade name: Cadura E-10P) were added to the dispersed solution and reacted at 50 to 53 ° C for 5 hours. Acetone was removed under vacuum to give a dispersion having a solids content of 39-41 wt% and a pH of 8.1.

Example 3 Hydroxy Group-Containing Aqueous Polyurethane Dispersion

33.3 g of polycaprolactone polyol (trade name: DICAP 600), with polydimethylpropionate condensation-polymerized in the main chain having a number average molecular weight of 600 in a 2 L reaction vessel equipped with a heater, a cooler and a stirrer, a polytetramethylene polyol having a number average molecular weight of 2000 222.3 g (trade name: PTG2000) and 0.02 g of dibutyl tin dilaurate were added and homogenized at 100 ° C for 30 minutes. Next, it cooled to 80 degreeC, 77 g of isophorone diisocyanate and 14.6 g of hexamethylene diisocyanate were added, and it was made to react at 80-85 degreeC for 60 minutes. Subsequently, 18.5 g of siloxane polyol (trade name: FM-DA11) containing a bifunctional hydroxy group having a number average molecular weight of 1000 was added thereto, and the mixture was reacted at 85 ° C until the isocyanate content was 4.75%. After cooling to 50 ° C. and completely homogenized by adding 600 g of anhydrous acetone, 80 ° C. of water, 17.3 g of α, ω-polypropyleneglycoldiamine-sulfonated sodium salt and 13.6 g of 80% aqueous hydrazine solution were used at 40 ° C. The mixture was added and reacted at 40 ° C. until no NCO was observed. Then, 513 g of water was added thereto, followed by dispersion by high speed stirring. 0.11 g of a catalyst tetrabutylammonium chloride and 10 g of a monofunctional epoxy compound (trade name: Cadura E-10P) were added to the dispersed solution and reacted at 50 to 53 ° C for 5 hours. Acetone was removed under vacuum to give a dispersion having a solids content of 39-41 wt% and a pH of 7.9.

Example 4 Hydroxy Group-Containing Aqueous Polyurethane Dispersion

33.3 g of polycaprolactone polyol (trade name: DICAP 600), with polydimethylpropionate condensation-polymerized in the main chain having a number average molecular weight of 600 in a 2 L reaction vessel equipped with a heater, a cooler and a stirrer, a polytetramethylene polyol having a number average molecular weight of 2000 111.2 g of a polycarbonate polyol having a number average molecular weight of 2000 (brand name: PCDL L6002) 111.2 g of dibutyl tin dilaurate was added and homogenized at 100 ° C for 30 minutes. Next, it cooled to 80 degreeC, 77 g of isophorone diisocyanate and 14.6 g of hexamethylene diisocyanate were added, and it was made to react at 80-85 degreeC for 60 minutes. Subsequently, 18.5 g of siloxane polyol (trade name: FM-DA11) containing a bifunctional hydroxy group having a number average molecular weight of 1000 was added thereto, and the mixture was reacted at 85 ° C until the isocyanate content was 4.75%. After cooling to 50 ° C. and completely homogenized by adding 600 g of anhydrous acetone, 80 ° C. of water, 17.3 g of α, ω-polypropyleneglycoldiamine-sulfonated sodium salt and 13.6 g of 80% aqueous hydrazine solution were used at 40 ° C. The mixture was added and reacted at 40 ° C. until no NCO was observed. Then it was dispersed by high stirring with the addition of 513.4 g of water. 0.11 g of a catalyst tetrabutylammonium chloride and 10 g of a monofunctional epoxy compound (trade name: Cadura E-10P) were added to the dispersed solution and reacted at 50 to 53 ° C for 5 hours. Acetone was removed under vacuum to give a dispersion having a solids content of 39-41 wt% and a pH of 8.0.

Comparative Example 1

32.6 g of polycaprolactone polyol (trade name: DICAP 600), with polydimethylpropropionate condensation-polymerized in the main chain having a number average molecular weight of 600 in a 2 L reaction vessel equipped with a heater, a cooler and a stirrer, a polytetramethylene polyol having a number average molecular weight of 2000 126.6 g of a polycarbonate polyol having a number average molecular weight of 2000 (brand name: PTG2000) (trade name: PCDL L6002) 126.6 g of dibutyl tin dilaurate was added and homogenized at 100 ° C for 30 minutes. Subsequently, the mixture was cooled to 80 ° C., and 75.5 g of isophorone diisocyanate and 14.3 g of hexamethylene diisocyanate were added and reacted at 85 ° C. until the isocyanate content was 4.53%. The mixture was cooled to 50 ° C. and completely homogenized by adding 600 g of anhydrous acetone. Then, a mixture of 80 g of water, 17.6 g of α, ω-polypropylene glycoldiamine-sulfonated sodium salt and 13.3 g of 80% aqueous hydrazine solution at 40 ° C. Was added and reacted at 40 ° C. until no NCO was observed. Then it was dispersed by high stirring with the addition of 513.5 g of water. Acetone was removed under vacuum to give a dispersion having a solids content of 39-41 wt% and a pH of 6.8.

Comparative Example 2

A 2L reaction vessel equipped with a heater, a cooler and a stirrer was added 299.5 g of dicarbonate tin dilaurate having a number average molecular weight of 2000 (brand name: PCDL L6002) and homogenized at 100 ° C. for 30 minutes. Subsequently, the mixture was cooled to 80 ° C, and 64.6 g of isophorone diisocyanate and 12.2 g of hexamethylene diisocyanate were added, followed by reaction until the isocyanate content was 3.87% at 80 to 85 ° C. After cooling to 50 ° C. and completely homogenizing by adding 600 g of anhydrous acetone, at 40 ° C., 80 g of water, 17.8 g of α, ω-polypropylene glycoldiamine-sulfonated sodium salt, and 11.4 g of 80% aqueous hydrazine solution were used. The mixture was added and reacted at 40 ° C. until no NCO was observed. It was then dispersed by high stirring with the addition of 514.4 g of water. Acetone was removed under vacuum to give a dispersion having a solids content of 39-41 wt% and a pH of 6.9.

Comparative Example 3

The solids content is 39-41% by weight, a pH of 7.0, the outflow time in 70 seconds or less 23 ℃ hydroxy group was used a polyurethane dispersion is Bayhydrol ^® PR-240 - an aliphatic polyester-free.

[Production Examples 1 to 12] and [Comparative Production Examples 1 to 9]

Preparation Examples 1 to 12 by conventional methods known in the art according to the compositions shown in Tables 1 and 2 using the aqueous dispersion prepared in Reference Examples 1 to 3, Examples 1 to 4 and Comparative Examples 1 to 3 And the soft coating solutions of Comparative Production Examples 1 to 9 were prepared.

Production Example One 2 3 4 5 6 7 8 9 10 11 12 subject Example 1 18.3 18.3 18.3 Example 2 18.3 18.3 18.3 Example 3 18.3 18.3 18.3 Example 4 18.3 18.3 18.3 Polyester-urethane dispersion 1 (reference example 1) 27.5 27.5 27.5 27.5 Polyester-urethane dispersion 2 (reference example 2) 27.5 27.5 27.5 27.5 Polyester-urethane dispersion 3 (reference example 3) 20 20 20 20 BYK-346 0.5 Tinuvin 1130 0.4 Matte 44 PUR 41 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.3 0.3 0.3 0.3 H ₂ O One 8.4 Formex 825 0.2 DPnB 0.4 Hardener Polyisocyanate mixture 7.5

Comparative Production Example One 2 3 4 5 6 7 8 9 Comparative Example 1 18.3 18.3 18.3 Comparative Example 2 18.3 18.3 18.3 Comparative Example 3 18.3 18.3 18.3 Polyester-urethane dispersion 1 (reference example 1) 27.5 27.5 27.5 Polyester-urethane dispersion 2 (reference example 2) 27.5 27.5 27.5 Polyester-urethane dispersion 3 (reference example 3) 20 20 20 BYK-346 0.5 Tinuvin 1130 0.4 Matte 44 PUR 41 0.2 0.2 0.2 0.2 0.2 0.2 0.3 0.3 0.3 H ₂ O One 8.4 Formex 825 0.3 DPnB 0.4 Hardener Polyisocyanate mixture 7.5

The raw material and symbol in Table 1 and Table 2 are as follows.

BYK-346: Wetting enhancer (BYK-Chemie)

Tinuvin 1130: Benzotriazole UV absorber (Ciba)

Matting agent: Paste with high speed dispersion of Acematt TS-100 / Disperbyk 190 / H ₂ O: 1 / 0.4 / 9.6

PUR 41: Urethane Thickener (Munzing)

Foamex 825: modified siloxane antifoaming agent (Tego Chemie)

DPnB: Dipropylene glycol n-propyl ether

Polyisocyanate mixture: A mixture of Bayhydur 3100 and Bayhydur VPLS 2306 mixed in a weight ratio of 33:67 and diluted with a propylene glycol monobutyl ether acetate solvent (solid content: 75%).

Test Example 1 Coating Property Evaluation

After washing with a toluene / isopropyl alcohol (1: 1) solution on a polypropylene panel, apply 5-10 μm of primer with a modified chlorinated olefin emulsion, and dried at 80 ° C. for 20 minutes. -12 and Comparative Production Examples 1-9 were sprayed, coated to a thickness of 20-40 µm, dried at 80 ° C for 30 minutes, and evaluated for coating properties.

<Room temperature adhesion test>

After cross-cutting 11 cuts at 2 mm intervals in the horizontal and vertical directions on the specimen, clean the surface with a soft brush and securely attach it with the specified tape of the appropriate width and length. The number of coating scales peeled off by pulling strongly was leaked. Also called the checkerboard adhesion test, the greater the number of peelings on a total of 100 checkerboard scales, the poorer the adhesion.

<Sunscreen resistance test>

Two sheets of white cloth of the same size were stacked on an acrylic plate (50 × 50 mm), and 0.25 g of sunscreen (NIVEA SPF 47) was applied to the entire surface. The sunscreen application site was placed on the coated specimen and pressed against the acrylic plate. After leaving for 1 hour in a thermostat at 80 ± 2 ° C., it was taken out to remove the white cloth and the acrylic plate. After standing at room temperature for about 10 to 15 minutes, washed with a neutral detergent and dried. The surface state of the coating film was investigated and an adhesion test was performed immediately.

<Dry Wear Test>

Using a reciprocating wear tester, the test load was checked using a double-sided cloth friction material under the conditions of 1 kg _f test load, 30 reciprocating speed / minute, and 100 mm friction stroke, and the number of tests was examined.

Coating properties were evaluated for five specimens of each test and the average values are shown in Tables 3 and 4.

Production Example One 2 3 4 5 6 7 8 9 10 11 12 Room temperature 0 0 0 0 0 0 0 0 0 0 0 0 Sun Cream Resistance 0 0 0 0 0 0 0 0 3 5 4 5 Dry Wear Test 1700 1760 1500 1450 1530 1630 1520 1410 1020 1120 1030 1010

Comparative Production Example One 2 3 4 5 6 7 8 9 Room temperature 0 0 0 0 0 0 0 0 0 Sun Cream Resistance 6 7 7 8 5 8 10 18 16 Dry Wear Test 1200 1120 1250 1040 1030 1010 800 680 770

In the results of Tables 3 and 4, Comparative Examples 1 to 12 containing the hydroxy-containing aqueous polyurethane dispersion according to the present invention contained the same polyester-urethane dispersion (Reference Examples 1 to 3). It was confirmed that sunscreen resistance and abrasion resistance were better than -9.

Claims (6)

1) reacting a polyol mixture of two or more kinds of polyols including polycaprolactone, polycarbonate, polysiloxane glycol or polytetramethylene glycol with polyisocyanate; 2) preparing a polyurethane by reacting the reactant of step 1 with a polyamine having a sulfonic acid salt, and then dispersing the polyurethane in water to prepare a polyurethane dispersion; And 3) reacting the dispersion of step 2) with a monofunctional epoxy compound having a number average molecular weight of 100-300 to prepare an aqueous polyurethane containing a hydroxyl group in the polyurethane chain. Method for producing a hydroxyl group-containing aqueous polyurethane dispersion for soft coating. The dispersion according to claim 1, wherein the dispersion is contained in an aqueous polyurethane resin solids content of 60 to 80 wt%, 20 to 30 wt% polyisocyanate, 1 to 9 wt% polyamine, and 1 to 5 wt% monofunctional epoxy compound. Method for producing a hydroxyl group-containing aqueous polyurethane dispersion for soft coating. The method according to claim 1, wherein the polyamine is α, ω-polypropylene glycoldiamine-sulfonated containing Na, K, Li or Ca metal. The method of claim 1, wherein the epoxy compound is a monofunctional epoxy compound having a number average molecular weight of 100 to 300. A hydroxyl group-containing aqueous polyurethane dispersion for soft coating prepared by the method according to any one of claims 1 to 4. A soft coating composition containing the hydroxyl group-containing aqueous polyurethane dispersion according to claim 5.